I can't remember when there's been so much speculation about what the future holds for working life. Or when those who imagine they know what the future holds have worked so hard to scare the dickens out of our kids.

Getting on for 100 years ago – 1930, to be precise – the father of macro-economics, John Maynard Keynes, wrote an essay, Economic Possibilities for our Grandchildren, in which he calculated that if technological progress produced real economic growth per person averaging 2 per cent a year for 100 years, by then people would enjoy a comfortable standard of living while needing to work only 15 hours a week.